This proposal tested the hypothesis that misoprostol attenuates the rise in blood pressure induced by diclofenac sodium (a non-steroidal anti-inflammatory drug) in elderly patients with salt-sensitive, stage I-II essential hypertension. Misoprostol is a prostaglandin E2 analog that had been shown to attenuate the effects of single-dose oral ibuprofen on glomerular filtration rate, renal blood flow, and on blood pressure. This study, conceived by the Principal Investigator, was supported by an unrestricted grant-in-aid from the Searle pharmaceutical company. The proposal was considered an investigator-initiated, hypothesis-oriented study generated by the Principal Investigator and his associates, and was not considered to be a drug company-sponsored clinical trial. This study has been completed, and the hypothesis confirmed.